Cutting tools having pin-type holding means for retaining indexable, replaceable inserts in a toolholder are commonly used. In such cutting tools, a pin typically projects into a central hole in the cutting insert and holds the insert against a shoulder of the toolholder. Various pin and toolholder configurations and mechanisms have been developed to achieve holding of the cutting insert against the toolholder shoulder.
The Kelm U.S. Pat. Nos. 3,341,920, 3,341,921 and 3,341,923 issued Sept. 19, 1967 disclose a pin with a conical seat portion adapted to engage a conical recess in the toolholder to cause the pin to move toward a shoulder thereon when the pin is screwed into a tapped hole in the toolholder. Pin movement toward the shoulder is effected by offsetting the conical recess relative to the tapped hole and effects clamping of the cutting insert against the shoulder. An annular shoulder is provided on the insert retention pin for the purpose of retaining an insert seat on the toolholder when the cutting insert is being replaced. The Diemond et al. U.S. Pat. No. 3,310,859 issued Mar. 28, 1962 describes a somewhat similar retention pin/toolholder arrangement.
The Gustafson U.S. Pat. No. 3,623,201 issued Nov. 30, 1971 describes a cutting tool in which the retention pin is provided with an annular, radially-oriented shoulder which engages against an annular shim around their entire peripheries when the pin is threaded into a tapped hole in the toolholder to clamp a cutting insert against a shoulder on the toolholder. The axis of the tapped hole into which the retention pin is threaded is inclined relative to the insert seat on the toolholder so that the radial shoulder of the retention pin engages the shim, which is parallel to insert seat surface, at an angle and bends the retention pin toward the shoulder of the toolholder as it is threaded into the tapped hole, the pin shoulder eventually seating on the shim around their entire peripheries.
The Kaiser U.S. Pat. No. 3,296,683 issued Jan. 10, 1967 provides a cutting tool having a threaded clamping bolt received in a tapped hole oriented at an angle in the toolholder and an annular clamping washer beneath the bolt head for engaging on one side a crescent-shaped surface formed in the toolholder as the bolt is screwed into the tapped hole and for engaging on the other side a cutting blade to clamp it against the toolholder. The crescent-shaped surface is at an inclination to the plane of the toolholder so that the high point or central portion of the surface forms a fulcrum for the washer whereby the vertical side of the cutting blade is engaged against the vertical side of the toolholder.
Other examples of cutting tools of the general type described are illustrated as well as similar types in the following patents:
______________________________________ U.S. Pat. No. Issued ______________________________________ 1,838,520 Dec. 29, 1931 2,598,581 May 27, 1952 3,097,417 July 16, 1963 3,173,191 Mar. 16, 1965 3,187,406 June 8, 1965 3,268,978 Aug. 30, 1966 3,284,874 Nov. 15, 1966 3,299,489 Jan. 24, 1967 3,310,859 Mar. 28, 1967 3,320,654 May 23, 1967 3,341,919 Sep. 19, 1967 3,368,265 Feb. 13, 1968 3,408,722 Nov. 5, 1968 3,416,209 Dec. 17, 1968 3,488,822 Jan. 13, 1970 3,491,421 Jan. 27, 1970 3,540,102 Nov. 17, 1970 3,654,682 Apr. 11, 1972 3,662,444 May 16, 1972 3,672,016 June 27, 1972 3,815,195 June 11, 1974 3,946,473 Mar. 30, 1976 3,997,951 Dec. 21, 1976 4,189,264 Feb. 19, 1980 4,200,416 Apr. 29, 1980 4,220,428 Sept. 2, 1980 4,244,666 Jan. 13, 1982 4,245,937 Jan. 20, 1981 ______________________________________